Hello and thank you for reaching out. I'm going to be honest I did not read this whole thing but I did have a response to your general question.
I don't think smoking anything is really a sin, I think it can become sinful if it is abused or becomes an addiction. Similarly with drinking, in the Bible drinking was like an everyday thing but what was wrong was when you became drunk. Jesus says our bodies are temples and so we should honor them and be mindful of what we put in them.
You are right. Our bodies are the temple of the Holy Spirit.
The religions that teach drug use, use them to summon demons. The drugs open the door to them.
Believe it or not, there are Satanists who pretend to be Christian so they can infiltrate and influence us.
I caught a pagan, Hindu, Catholic and a homosexual who worked with children at a Non-denominational mega church that I used to attend. The church was into attraction of the world with rock concerts and contemporary atmosphere/ techniques. The pastor was into the love of money. Some workers were not vetted properly at all.
I left the church finally after my hearing was permanently damaged from the contemporary Christian music blasted. They had a disclaimer that the decibel level met OSHA limits. Misleading bec ause it harmed more than just me.
Back in time....
In my adolescence, 11-12, some adults tempted me to smoke pot. I was shocked to find out that one best friend was a Satanist. He had a marble alter, crucified animals to blaspheme Jesus. I had no idea for those years until he came out of the closet. He was a lawyer.
I am very fortunate that someone cared about me enough to lead me to Christ when I was in my mid teens.
I
Got Saved.<
It was a children's preacher from an independent Baptist Church. Shout out to Mike Deem.


I'm glad that it was the kind of church that cared enough to point out moral boundaries.
That pastor didn't preach to cater to the flesh and ego to get a huge crowd. We were more interested in the Word of God .
The Lord used that preaching to help encourage me to read my Bible, and give up the "friends" who influenced me to smoke and drink alcohol. Those friends destroyed their lives.
By the kindness of our Father, He helped me become an athlete and start my own Martial Art and Fitness System. This helps with self discipline and a lot more.
I was chosen to start a College and Career Ministry in my church. That provided a group of peers that were not perfect but better than the University setting.
I would suggest finding a church/pastor that preaches against drugs and alcohol, has the right gospel and is conservative in morality. They might even have a college group too.
Welcome to the forum and looking forward to reading more of your posts.